Evolution of Southern California Landscapes

The semi-arid climate of inland Southern California with its historically cool, wet winters and hot, dry summers has been described as a gardener’s paradise. In the last two centuries, the mild climate paired with plentiful resources allowed us to design gardens to match every style, from the lush lawns and water-loving trees often found in formal Colonial and English gardens to the informal Cottage and Romantic style gardens where grasses, flowering perennials and shrubs predominate. Southern California yards were often high water-using, lush, wet, and dark green year around.

During the postwar building boom in California, water was inexpensive and seen as a relatively unlimited resource. Thirsty lawns, framed by exotic trees and shrubs were installed by home builders who knew how a carpet of turf, foundation shrubs, and maybe a tree as a focal point could create curb appeal and make small lots look larger. Homeowners were assured that all their landscapes would thrive using a few sprinklers and maybe the occasional pest control potion from the hardware store.

By the mid-1980s, a major mindset shift began to occur, drawing attention to dwindling water supplies, drought, and a need to conserve water indoors and outdoors. Our groundwater aquifers were being depleted faster than they were being replenished and our reliance on imported water was taking a toll on the ecosystems of the Sacramento-San Joaquin Delta and Colorado River watersheds.

In the 1990s, researchers became aware of pesticide pollution resulting from urban landscape runoff. It is now recognized as one of several key sources of waterway pollution that leads to unhealthy ecosystems for pollinators, birds, pets, and humans.

Over the past decade, a greater emphasis has been placed on water-efficient landscapes due to drought, dwindling water supplies, higher water costs, stormwater pollution, and climate change.